The pope has basked in an emotional send off from a massive crowd at his final general audience in St Peter's Square, recalling moments of "joy and light" but also times of difficulty when "it seemed like the Lord was sleeping."
An estimated 150,000 people, many with banners saying "Grazie!", jammed the piazza to bid Benedict farewell and hear his final speech as pontiff. In this appointment - which he has kept each week for eight years to teach the world about the Catholic faith - Benedict gave deep thanks to his flock for respecting his decision to retire.
Benedict clearly enjoyed the crowds, taking a long victory lap around the square in an open-sided car and stopping to kiss and bless half a dozen children handed to him by his secretary. A total of 70 cardinals, some tearful, sat in attendance.
But Benedict made a quick exit, foregoing the typical meet-and-greet session that follows the audience; the Vatican has said there were simply too many people who would have wanted to say goodbye.
Given the historic moment, Benedict also changed course and did not produce his typical professorial Wednesday catechism lesson. Rather, he made his final public appearance in St Peter's a personal one, explaining once again why he was becoming the first pope in 600 years to resign and urging the faithful to pray for his successor. "To love the church means also to have the courage to take difficult, painful decisions, always keeping the good of the church in mind, not oneself," Benedict said to thundering applause.
He noted that a pope has no privacy: "He belongs always and forever to everyone, to the whole church." But the pope promised that in retirement he would not be returning to private life - instead taking on a new experience of service to the church through prayer. He recalled that when he was elected pope on April 19, 2005, he questioned if God truly wanted it. "It's a great burden that you've placed on my shoulders," he recalled telling God.
During his eight years as pope, Benedict said, "I have had moments of joy and light, but also moments that haven't been easy ... moments of turbulent seas and rough winds, as has occurred in the history of the church when it seemed like the Lord was sleeping."
But he said he never felt alone, that God always guided him, and he thanked his cardinals and colleagues for their support and for "understanding and respecting this important decision."
Under a bright sun and blue skies, the square was overflowing with pilgrims and curiosity-seekers. Those who could not get in picked spots along the main boulevard leading to the square to watch the event on giant TV screens. Some 50,000 tickets were requested for Benedict's final master class. In the end, the Vatican estimated that 150,000 people flocked to the farewell.
Benedict has said he decided to retire after realising that, at 85, he simply did not have the "strength of mind or body" to carry on. "I have taken this step with the full understanding of the seriousness and also novelty of the decision, but with a profound serenity in my soul," Benedict told the crowd.